Question

kubectl get命令使用此标志-o来格式化输出。

是否有类似的方法来格式化kubectl describe命令的输出？

例如：

kubectl describe -o="jsonpath={...}" pods my-rc

将为my-rc复制控制器中的pod列表打印JSON格式。但-o命令不接受describe。

Answer 1

kubectl describe不支持-o或同等效果。它意味着人类可读而不是脚本友好。您可以使用kubectl get pods -l <selector_of_your_rc> -o <output_format>实现所描述的内容，例如：

$ kubectl get pods -l app=guestbook,tier=frontend -o name
pod/frontend-a4kjz
pod/frontend-am1ua
pod/frontend-yz2dq

Answer 2

就我而言，我需要从服务中获取负载均衡器地址。我是使用kubectl get service：

完成的

$ kubectl -n <namespace> -ojson get service <service>

{
    "apiVersion": "v1",
    "kind": "Service",
    [...]
    "status": {
        "loadBalancer": {
            "ingress": [
                {
                    "hostname": "internal-xxxxxxxxxxxxxxxxxxxxxxxxxxx-yyyyyyyyyy.us-east-1.elb.amazonaws.com"
                }
     [...]
}

Answer 3

根据kubectl help describe的输出，它看起来不支持结构化输出：

$ kubectl help describe
Show details of a specific resource or group of resources.

This command joins many API calls together to form a detailed description of a
given resource or group of resources.

$ kubectl describe TYPE NAME_PREFIX

will first check for an exact match on TYPE and NAME_PREFIX. If no such resource
exists, it will output details for every resource that has a name prefixed with NAME_PREFIX

Possible resource types include (case insensitive): pods (po), services (svc), deployments,
replicasets (rs), replicationcontrollers (rc), nodes (no), events (ev), limitranges (limits),
persistentvolumes (pv), persistentvolumeclaims (pvc), resourcequotas (quota), namespaces (ns),
serviceaccounts, ingresses (ing), horizontalpodautoscalers (hpa), daemonsets (ds), configmaps,
componentstatuses (cs), endpoints (ep), and secrets.

Usage:
  kubectl describe (-f FILENAME | TYPE [NAME_PREFIX | -l label] | TYPE/NAME) [flags]

Examples:
# Describe a node
kubectl describe nodes kubernetes-minion-emt8.c.myproject.internal

# Describe a pod
kubectl describe pods/nginx

# Describe a pod identified by type and name in "pod.json"
kubectl describe -f pod.json

# Describe all pods
kubectl describe pods

# Describe pods by label name=myLabel
kubectl describe po -l name=myLabel

# Describe all pods managed by the 'frontend' replication controller (rc-created pods
# get the name of the rc as a prefix in the pod the name).
kubectl describe pods frontend

Flags:
  -f, --filename=[]: Filename, directory, or URL to a file containing the resource to describe
  -l, --selector="": Selector (label query) to filter on

Global Flags:
      --alsologtostderr[=false]: log to standard error as well as files
      --certificate-authority="": Path to a cert. file for the certificate authority.
      --client-certificate="": Path to a client certificate file for TLS.
      --client-key="": Path to a client key file for TLS.
      --cluster="": The name of the kubeconfig cluster to use
      --context="": The name of the kubeconfig context to use
      --insecure-skip-tls-verify[=false]: If true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure.
      --kubeconfig="": Path to the kubeconfig file to use for CLI requests.
      --log-backtrace-at=:0: when logging hits line file:N, emit a stack trace
      --log-dir="": If non-empty, write log files in this directory
      --log-flush-frequency=5s: Maximum number of seconds between log flushes
      --logtostderr[=true]: log to standard error instead of files
      --match-server-version[=false]: Require server version to match client version
      --namespace="": If present, the namespace scope for this CLI request.
      --password="": Password for basic authentication to the API server.
  -s, --server="": The address and port of the Kubernetes API server
      --stderrthreshold=2: logs at or above this threshold go to stderr
      --token="": Bearer token for authentication to the API server.
      --user="": The name of the kubeconfig user to use
      --username="": Username for basic authentication to the API server.
      --v=0: log level for V logs
      --vmodule=: comma-separated list of pattern=N settings for file-filtered logging

Answer 4

如@janekuto建议

describe无法用于显示json格式的数据

请参阅我的答案here。 jq实际上是一个功能强大的实用程序，可以处理kubectl的json显示。您可以jq做很多事情而无需付出太多努力。

kubectl - format the resource quota values in json format

Answer 5

kubectl 不支持 -o yaml/json for describe，但您仍然可以使用其他一些命令来获取 describe 中的信息，例如：

kubectl get events

如何将kubectl describe的输出格式化为JSON

5 个答案: